Now when he had spent everything, a severe famine occurred in that country, and he began to be impoverished. So he went and [b]hired himself out to one of the citizens of that country, and he sent him into his fields to feed swine. Luke 15:14-15 (NASB)

The other day I blogged about people who are difficult to love. People that are unloving, not thankful, hostile, selfish, and a host of other ungodly things. Sometimes it is your parent or spouse, and other times it is your child who fits the description.

I am not saying these people are beyond redemption, or that they are incapable of being loved. I am saying that their actions and attitudes have brought your relationship to the point where every aspect of your relationship with them is painful, hostile, and adversarial. The only person they appear to care about is themselves and they give little thought or care to how they affect you. You love them deeply, and you are concerned for them. You want to love them otherwise you would not be hanging in there.
They make it very, very difficult. Your love is often not returned or acknowledged, they treat you as though you “owe” them, there is so little respect for you or your wishes, they lie to you, sometimes steal from you, and hurt you all the time. All they appear to care about is how you affect them. Your loved one is supremely selfish and self-focused.
You have to remember that when Jesus gave His life for all of us, we were extremely unlovely. We were filthy horrific sinners and smelled of death. Our task is the same one in application that Jesus performed. While we cannot save them from their sin or from themselves, the task before us is to love the unlovely. Can you recognize and accept why Christ has given you the burden for this person? (good question!) In what ways does this persons unlovliness remind you of a time when you were similarly unlovely?

Another question I have for you is, can you glory in the cross you carry for the joy set before you of being conformed to Christ-likeness? Can you accept their place in your life as being a tool God is using to change your heart?

Often, we try (and fail) to change them. And while some behavioral changes can take place and seem to stick for a while- sadly they don’t last. Those who are the beneficiaries of some good Bible centered counsel know that behavior change is only temporary.
When you love an unlovable person you must pray that God will capture their heart. You know you cannot change them at all. As much as you want to change their actions or attitude, particularly toward you, you must realize you cannot. Only One can change them, only He can change them. So you pray, and pray that they will somehow want to change to conform to the image of Christ. You hope and pray that something, anything will cause them to long for Him more than anything else they desire. If prayer appears to go unanswered it becomes depressing and discouraging. Most people quit because they can’t stand the discouragement.
Chuck Swindol points out that the ending of the book of Hosea does not have a happy ending, but rather leaves you hanging, wondering what the end of their story is. We never know if Gomer repents and turns only to Hosea and remains faithful, but we do know that Hosea was faithful to her.
The only form of Christ- likeness that person may recognize is your devotion to them. You have a magnificent opportunity to reflect Christ. 
Loving them does not mean enabling their sin or protecting them from consequences. Loving them can mean they wallow with the pigs while you prayerfully wait for repentance.